No. 1/March 25, 1997
New Corn Herbicides for 1997
Several new herbicides will be available for use in corn during the 1997 growing season. Some are new premixes of older active ingredients, some are new names of previously available products, and some are actually new active ingredients.
Basis Gold 89.5DF, a premix of rimsulfuron (in Basis), nicosulfuron (Accent), and atrazine, is used postemergence at 14 oz/A for grass and broadleaf weed control. Basis Gold may be applied to corn up to 12 inches tall or with up to 6 collars, whichever is most restrictive.
FulTime 4L, a premix of encapsulated acetochlor (TopNotch) plus atrazine, is applied early preplant (up to 40 days) or preemergence at 2.5 to 5 qt/A for grass and broadleaf weed control. FulTime has the same mixing and application restrictions as other products containing acetochlor.
Hornet 86DF, a premix of flumetsulfam (Broadstrike) and clopyralid (Stinger), may be soil-applied at 3.2 to 4.8 oz/A or foliar-applied at 1.6 to 4 oz/A for broadleaf weed control. During 1996, this product was sold under the trade name Broadstrike Plus.
Liberty 1.67E (glufosinate) is applied postemergence only to corn hybrids resistant to glufosinate (Liberty Link or Dekalb GR), at 20 to 28 fl oz/A. Liberty is a contact herbicide with no residual control. It may be sequentially applied after an acetamide herbicide for grass control, tank-mixed with atrazine, or split-applied. The preferred programs will likely be 1.5 lb a.i. atrazine preemergence, followed by Liberty postemergence or a tank mix of atrazine (0.75 to 1 lb a.i.) with Liberty as a total postemergence program.
Lightning 7ODG (imazethapyr + imazapyr) may receive a label in time for use in 1997 as a postemergence herbicide in IMI (IR- or IT-designated) corn hybrids. Lightning provides better control of some annual grasses and lambsquarters than does imazethapyr (Pursuit) alone.
Balance 75DF (isoxaflutole) is a soil-applied pigment-synthesis-inhibiting herbicide for corn. Clearance is not expected in time for 1997 use; but, when labeled, the use rate will be 1 to 4 oz/A. It will probably often be mixed with atrazine for cocklebur control or with a partial rate of an acetamide herbicide to improve grass control.
Axiom 68DF (4:1 thiafluamide: metribuzin) will not be labeled until 1998. Use rate will be 12 to 24 oz/A as a soil-applied or early postemergence herbicide for grass control. Some control of certain small-seeded broadleaf species can be expected.
Headline B &G is a copack of Poast Plus and Laddok for use on sethoxydim-resistant (SR) corn.
CyPro and CyPro AT are generic brands of cyanazine (Bladex) and Extrazine (cyanazine + atrazine), respectively.
Bromox and Moxy are generic brands of Buctril (bromoxynil), while Bromox AT and Moxy AT are generic brands of Buctril (bromoxynil) + Atrazine.
Dual II Magnum 7.63E contains the active isomer of metolachlor. The use rate will be 62.5% of the old Dual II active ingredient rates. In 1997, sales will likely be in states other than Illinois.
Changes in cyanazine and atrazine use restrictions:
Cyanazine rates limits are 5, 3, and 1 lb a.i./A for 1997, 1998, and 1999, respectively. This restriction has very little effect on 1997 use of Bladex and Extrazine II but will limit their use in 1998 and 1999.
Atrazine or cyanazine 66-foot setback restrictions around standpipes in tileoutlet terraced fields will not have to be met if the herbicide is immediately incorporated into the soil or is applied to a no-till field with a high amount of crop residue.
Marshal McGlamery and Aaron Hager, Department of Crop Sciences, (217)333-4424